An epoxy‐ended hyperbranched polymer as a new modifier for toughening and reinforcing in epoxy resin

A new epoxy‐ended hyperbranched polyether (HBPEE) with aromatic skeletons was synthesized through one‐step proton transfer polymerization. The structure of HBPEE was confirmed by Fourier transform infrared spectroscopy (FTIR), and nuclear magnetic resonance (NMR) measurements. It was proved to be one high efficient modifier in toughening and reinforcing epoxy matrix. In particular, unlike most other hyperbranched modifiers, the glass transition temperature (T_g) was also increased. Compared with the neat DGEBA, the hybrid curing systems showed excellent balanced mechanical properties at 5 wt % HBPEE loading. The great improvements were attributed to the increased cross‐linking density, rigid skeletons, and the molecule‐scale cavities brought by the reactive HBPEE, which were confirmed by dynamical mechanical analysis (DMA) and thermal mechanical analysis (TMA). Furthermore, because of the reactivity of HBPEE, the hybrids inclined to form a homogenous system after the curing. DMA and scanning electron microscopy (SEM) results revealed that no phase separation occurred in the DGEBA/HBPEE hybrids after the introduction of reactive HBPEE. SEM also confirmed that the addition of HBPEE could enhance the toughness of epoxy materials as evident from fibril formation. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 130: 1064‐1073, 2013     

Synthesis of a branched photosensitive copolymer and its application for negative‐type photoresists

Novel branched copolymers, poly(styrene‐alt‐maleic anhydride) (BPSMA), were synthesized through mercapto chain‐transfer polymerization with styrene, maleic anhydride (MA), and 4‐vinyl benzyl thiol (VBT). Then, the hydroxyl of hydroxyethyl methacrylate was reacted with MA to synthesize branched photosensitive copolymers, p‐BPSMAs. Fourier transform IR spectroscopy and ¹H‐NMR indicated that the synthesis was successful. Gel permeation chromatography indicated that the molecular weight decreased with increasing content of VBT. The thermal properties were characterized by thermogravimetric analysis; the results show that the thermal decomposition temperature of the BPSMAs was greatly enhanced. Real‐time IR was used to evaluate the UV‐curable kinetics of the p‐BPSMAs; the results show that the p‐BPSMAs could rapidly photopolymerize under UV irradiation in the presence of photoinitiators. Moreover, the photoresist based on the p‐BPSMAs exhibited improved photosensitivity when the VBT content increased, and the photoresist with 12 mol % VBT content had a low value of the dose that retained 50% of the original film thickness (10 mJ/cm²), and a 50‐μm resolution could be achieved compared to a linear photoresist. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 42838.     

Acrylate-based photosensitive resin for stereolithographic three-dimensional printing

In this article, we report an acrylate-based three-dimensional (3D) printing stereolithography rapid-prototyping photosensitive resin with a low viscosity, small volumetric shrinkage, high photoreactivity, and excellent strength. The resin was a compound prepared with bisphenol A epoxy acrylate (BAEA) as the main matrix, 1,6-hexanediol diacrylate (HDDA) and tri(propylene glycol) diacrylate (TPGDA) as reactive diluents, pentaerythritol triacrylate (PETA) as the crosslinking agent, and 2-hydroxy-2-methyl propiophenone (1173) and diphenyl(2,4,6-trimethyl benzoyl)phosphine oxide (TPO) as photoinitiators. The photocuring kinetics of the resins with different photoinitiator types and loadings were studied via real-time IR spectroscopy, which provided insights into the optimization of photoinitiator composition and printing parameter settings. The results show that the content change of each component affected the viscosity of the photosensitive resin; this was accompanied by fluctuations in the volume shrinkage and mechanical strength of the cured products. Although an increase in the molar ratio of the reactive diluent remarkably reduced the viscosity of the photosensitive resin and thereby boosted photopolymerization, it also caused an increase in the volume shrinkage and a sacrifice of mechanical strength. Finally, as shown by a comparison of the other samples we studied, the resin composed of 30 mmol HDDA, 50 mmol TPGDA, 10 mmol PETA, 10 mmol BAEA, 2.5 mol % TPO, and 2.5 mol % 1173 achieved the best viscosity of 239.53 mPa s at 25 °C, the minimum shrinkage rate of 4.36%, and the maximum tensile strength of 43.19 MPa. The 3D printing curing products had the closest size to the design dimensions of the computer-aided design model; this indicated that the resin seemed to be a most promising candidate for 3D printing applications. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47487.     

Conversion and shrinkage analysis of acrylated hyperbranched polymer nanocomposites

The photo‐curing behavior of composites containing nanosized SiO₂ in an acrylated hyperbranched polymer matrix was investigated by means of photo differential scanning calorimetry. The chemical conversion data were analyzed using an autocatalytic model, paying close attention to the influence of composition and UV intensity. It was shown that the reaction order and the autocatalytic exponent were independent of UV intensity and filler fraction, whereas the rate constant showed strong intensity dependence, but weak filler dependence. Maximum conversion was independent of UV intensity, but was reduced when a filler was present. The dispersion state influenced the gel‐point of the composites, but had no influence on the overall cure kinetics. Cure shrinkage reduction of ～ 33% could be achieved by adding 20 vol% of filler. This was attributed to the reduced double bond conversion of the matrix due to the presence of the filler. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009     

Thermomechanical and chemorheology properties of a thermosetting acrylic/melamine clearcoat modified with a hyperbranched polymer

The work presented here aims at studying the thermomechanical and chemorheological properties of an automotive clearcoat containing an acrylic/melamine resin modified with a hyperbranched poly ester‐amide (HBP) additive. Rheological experiments were conducted at ambient (25°C) and curing temperature (140°C). Dynamic mechanical thermal analysis and hardness measurements were performed to reveal the influence of HBP content on the behavior of the cured samples. It was found that the viscosity of the resin containing HBP samples considerably decreased. Although curing degree and mechanical properties were improved at low HBP loadings, a reverse effect was seen at higher contents. Dynamic rheological results during curing showed that although low amount of HBP resulted in an early gel point (GP), higher HBP loading postponed the GP. This loading‐dependent behavior was explained by the influence of HBP on viscosity and reactivity of the system on which the curing performance was influenced oppositely. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Crystallization behavior of hyperbranched polyethylenes with different degree of branching

Hyperbranched polyethylenes (HBPEs) with different degree of branching (DB) and similar M_n are used to investigate the effect of branch structure on their crystallization behaviors. The crystal structure, isothermal, and non‐isothermal crystallization kinetics of HBPEs are studied by X‐ray diffraction and differential scanning calorimetry. The isothermal crystallization process is analyzed by the Avrami equation while the non‐isothermal crystallization process is analyzed through the Ozawa and Mo methods. The XRD results indicate that the crystallization ability of HBPEs is weakened with the introduction of branch structure, i.e., the crystallinity of HBPEs decreases with the increase of DB, and even tends to zero. The kinetics results of isothermal and non‐isothermal crystallization verify the peculiar effects of DB on the crystallization process of HBPEs. In detail, a little of branch structure can accelerate the crystallization process of HBPEs, however a large number of branch can inhibit it. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2016 , 133, 44127.     

The structure and application of amine‐terminated hyperbranched polymer shale inhibitor for water‐based drilling fluid

Amine‐terminated hyperbranched polymer (HBP‐NH₂), as an inhibitor in water‐based drilling fluid, is prepared by the polycondensation of diamine AB₂ monomers. The primary amine and secondary amide structures are confirmed by Fourier transform infrared spectroscopy and nuclear magnetic resonance hydrogen spectroscopy. Through time of flight mass spectrometry, the molecular weight of HBP‐NH₂ is mainly distributed in the range of 200–1400. Also, the quasi‐spherical shape and the high temperature resistance (200 °C) performance of HBP‐NH₂ are, respectively, certified through the environmental scanning electron microscope and the thermogravimetric analysis. In the inhibition performance test, the linear expansion rate of sodium bentonite in 3 wt % HBP‐NH₂ aqueous solution is only 11.42%, which is lower than other inhibitors (KCl, FA‐367, and HPAM). Zeta potential analysis shows that HBP‐NH₂ has a strong ability to inhibit the hydration and dispersion of sodium bentonite by protonated primary amine groups. Compared with the base slurry, the absolute value of zeta potential is reduced by 25.5 mV in the slurry containing 3 wt % HBP‐NH₂ at 180 rpm. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45466.     

High biorenewable content acrylate photocurable resins for DLP 3D printing

Green chemistry and green engineering concepts have been combined to develop novel sustainable polymeric materials. Solvent free photocurable acrylate resins with biorenewable carbon content of 75%–82% suitable for application in DLP 3D printing technology were composed by commercially available bio-based materials, acrylated epoxidized soybean oil (AESO), isobornyl methacrylate (IBOMA), methacrylic ester (ME), tetrahydrofurfuryl acrylate (THFA), and tetrahydrofurfuryl methacrylate (THFMA). They demonstrated high printing accuracy and good adhesion between layers. The monitoring of photocross-linking kinetics of high biorenewable content acrylate photoresins by the real-time photorheometry and analysis of their rheological parameters was carried out. Synthesized polymers exhibited high yield of insoluble fraction and thermal decomposition temperature at the weight loss of 10% above 300°C. Polymers AESO/IBOMA and AESO/THFMA showed the highest values of tensile modulus and tensile strength. Biodegradability of the synthesized polymers AESO/ME, AESO/THFA, and AESO/THFMA was investigated by measuring oxygen consumption in a closed respirometer. Such AESO-based polymers can be a competitive solution to replace petroleum-derived polymeric materials in additive manufacturing and reduce the environmental impact.     

Synthesis of hyperbranched polybenzoxazoles and their molecular composites with epoxy resins

Hyperbranched aromatic polymers have attracted great attention recently because they combined the processability of hyperbranched polymers and the high‐level performance of aromatic polymers. Here, a one‐pot strategy for the synthesis of hyperbranched Polybenzoxazoles (HBPBOs) by polycondensation of 2,2‐Bis (3‐amino‐4‐hydroxyphenyl) hexafluoropropane and 1,3,5‐benzenetricarboxylic acid in Polyphosphoric acid was reported. The HBPBOs exhibited good solubility in organic solvents because of the branched structure and the flexible hexafluoropropane groups in main chains. The structure and terminal functional groups could be tailored by adjusting the molar ratio of two monomers. FT‐IR, NMR and XRD measurements confirmed the structure of HBPBOs, while thermogravimetric analysis (TGA), UV‐vis, and photoluminescence spectra, combined with the comparison with linear PBOs demonstrated the intriguing optical properties and good thermal stabilities of HBPBOs. The good solubility of HBPBOs also permitted their usage as molecular reinforcement for polymer composites as demonstrated in this study of HBPBOs/epoxy composites. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41942.     

Effect of generation number on properties of fluoroalkyl-terminated hyperbranched polyurethane latexs and its films

The 1–3 generations of hyperbranched polyesters (HBPE-1/2/3) were synthesized from trimethylolpropane (TMP) and 2,2-dimethylol propionic acid (DMPA) by “quasi-one-step method.” Then, isophorone diisocyanate (IPDI), polybutylene adipate (CMA-1044), DMPA and 1,4-butanediol (BDO) were utilized to prepare the urethane prepolymer (PU), which was reacted with HBPE to synthesize hyperbranched polyurethanes (HBPU). Finally, 1–3 generations of fluoroalkyl-end-capped hyperbranched polyurethanes (FHBPU) latexes were obtained by the reaction of perfluorohexyl ethanol (S104) and HBPU as well as the self-emulsification process. Structure of the products, the properties of different FHBPU emulsions and its films were investigated by FTIR, ¹H NMR, TEM, DLS, TGA, XPS, XRD, SEM, AFM and static contact angle measuring instrument. Results showed that the particle size of FHBPU latexes increased gradually with the increase of generation number. SEM and XRD results verified that an amount of the crystal particles was increased with the increase of generation number. XPS and AFM demonstrated that degree of microphase separation and film roughness was increased with the increase of branching degree. Static water contact angles could attain 95.9°, 100.3°, and 107.0°, respectively on the 1–3 generations of FHBPU films, compared to that on PU (75.1°).     

Lignin valorization by forming thermally stimulated shape memory copolymeric elastomers—Partially crystalline hyperbranched polymer as crosslinks

Lignin based thermal‐responsive elastomers were produced by a melt polycondensation reaction with a long alkyl chain hyperbranched poly(ester‐amine‐amide) (B₃‐A₂‐CB₃¹). The effect of lignin content on elastomers properties was investigated. The thermal and mechanical properties of the copolymers were characterized by DMA, DSC, and TGA. The morphology of the copolymer was examined by SEM. Tensile properties were dominated by HBP <25% lignin content while lignin dominated >25% content. The copolymers glass transition temperature (T_g) increased with lignin content. The elastomer with 30% lignin content demonstrated optimal mechanical properties (tensile strength 5.3 MPa, Young's modulus 8.9 MPa, strain at break 301%, and toughness 1.03 GPa). Thermally stimulated dual shape memory effects (SME) of the copolymers were quantified by cyclic thermomechanical tests. The transition temperature (T_trans) of the polymer was able to be controlled (room to body temperature) by varying the amount of lignin added which broadens the range to medical applications. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 41103.     

Synthesis of hyperbranched polymers by free radical addition‐coupling polymerization with A3/B2 and A2A′/B2 approaches

Two tribromide compounds, 1,3‐(propanoic acid, 2‐bromo‐)‐2‐(2‐bromo‐1‐oxopropylamino)propyl ester (A 1 ) and trimethylolpropane tris(2‐bromopropionate) (A 2 ), were synthesized. By Cu/N,N,N′,N′,N″‐pentamethyldiethylenetriamine (PMDETA)‐mediated radical addition‐coupling polymerization (RACP) of 2‐methyl‐2‐nitrosopropane (MNP) with the tribromide compounds, two types of hyperbranched polymers were synthesized under mild conditions, respectively. Polymerization degrees of the polymers increased with time gradually, which is in line with a step‐growth polymerization mechanism. By tracing the polymerization process by gel permeation chromatography and NMR analysis, proper reaction conditions to get hyperbranched polymers was obtained. Based on the results of NMR analysis on the polymer chain structure, mechanism of forming hyperbranched polymer has been proposed, which includes formation of carbon radicals from the tribromo monomer through single electron transfer, their reaction with MNP to form nitroxide radicals, and cross‐coupling reaction of the nitroxide radicals with other carbon radicals. The gelation point of the A 2 ‐MNP system is larger than that of the A 1 ‐MNP system, indicating that probability of intramolecular cyclization in A 2 ‐MNP RACP system is higher than the A 1 ‐MNP system. The reactivity of —NHCOCH(CH₃)Br group of A 1 is lower than its two —OCOCH(CH₃)Br groups, and this resulted in longer distance between two adjacent branch points in the hyperbranched polymer of A 1 ‐MNP than the A 2 ‐MNP system. It is possible to adjust the chain structure of RACP‐based hyperbranched polymer by changing the reactivity of the functional groups in A₃ monomer. © 2015 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41972.     

Preparation and characterization of printable solder resist inks based on hyperbranched polyester

Two novel solder resist inks containing hyperbranched epoxy resin (HBPE) for thermal curing and hyperbranched epoxy acrylate resin (HBPEA) for UV‐curing were introduced in this work. Different generations of HBPE and HBPEA were synthesized and their chemical structures were determined by FT‐IR. Both curing reactions were monitored under differential scanning calorimetry (DSC) and photo‐DSC. For HBPE, the curing temperature of 7th generation was only 91°C and for HBPEA, the curing duration of 7th generation was under 10 s. The thermal stabilities of cured resins were much more stable than linear resin, as the decomposition temperatures of HBPE and HBPEA were both over 400°C. The ink containing HBPE or HBPEA jetted by piezoelectric printer showed excellent accuracy and consistency of linewidth and the morphologies of cured pattern were observed through a stereo microscope. Other performances of solder masks were tested under China Printed Circuit Association (CPCA) standard (CPCA/JPCA 4306‐2011), which satisfy all requirements of printed circuit board soldering procedure. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41805.     

High-toughening modification of polylactic acid by long-chain hyperbranched polymers

The hyperbranched polyester synthesized by “one-step method” was grafted with stearic acid to obtain long-chain hyperbranched polymers (LCHBPs) with a large number of long stearic acid chains at the end. By means of FTIR and ¹³C-NMR characterization, it was proved that stearic acids were grafted onto hyperbranched polyesters (HBPE) to yield LCHBPs successfully. It was determined by GPC and hydroxyl value titration that the number average molecular weight of HBPE was 4.86 × 10³ and the grafting rate of stearic acid was 47%. Polylactic acid (PLA)/LCHBPs blends were prepared by melt processing method. The results showed that comparing with neat PLA, the tensile strength of PLA/LCHBPs blends decreased slightly with the increase of LCHBPs, but still maintained a high level, while the elongation at break and the impact strength of the PLA with 3.0 phr LCHBPs were greatly improved by 1360.0% and 119.8%, respectively. In addition, the impacted fracture characteristics of PLA changed significantly from brittle fracture to ductile fracture after LCHBPs incorporation, with the formation of a large number of filamentous structures. Thus, LCHBPs was an excellent toughening modifier for PLA and the resulting blends with improved performance possess wider applications.     

Synthesis of biomimetic hyperbranched zwitterionic polymers as targeting drug delivery carriers

Novel biomimetic hyperbranched copolymers that synthesized by polymerization of zwitterionic monomer (CBB) on the surface of a hyperbranched poly(3‐ethyl‐3‐(hydroxymethyl)oxetane) (HBPO) core and used as a drug delivery carrier have been investigated by analysis of protein‐adsorption‐resistance, cytotoxicity and cell type‐specific targeting properties. The as‐synthesized biomimetic hyperbranched copolymers showed low toxicity, favorable protein resistant properties and were ultrastable in 100% fetal bovine serum. Folic acid and rodiamin‐B were conjugated to the surface of synthesized micelles to endow it with target drug delivery and fluorescence activity, respectively. Intracellular uptake and in vitro cytotoxicity of HBPO‐poly(carboxybetaine) micelles were investigated. Doxorubicin was used as a model drug for Hela cells during the experiment. All results show that the biomimetic hyperbranched copolymer is a candidate carrier for target drug delivery. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Rheological properties of hydroxyl‐terminated and end‐capped aliphatic hyperbranched polyesters

The rheological behavior of two series of aliphatic hyperbranched (HB) polyesters, based on 2,2‐bis(hydroxymethyl)propionic acid (bis‐MPA) and di‐trimethylol propane (Di‐TMP) as a tetrafunctional core, was studied. The effect of the size (pseudo‐generation number, from second to eight) and structure on the melt rheological properties was investigated for a series of hydroxyl‐terminated HB polyesters. In addition, the influence of the nature and degree of modification of the terminal OH groups in a series of fourth‐generation polyesters end‐capped with short and long alkyl chains and some aryl groups on the rheological properties was analyzed. The time–temperature superposition procedure was applied for the construction of master curves and for the analysis of the rheological properties of HB polyesters. The data obtained from WLF analysis of the HB polyesters showed that the values of the thermal coefficient of expansion of free volume α_f and the fractional free volume at the glass transition temperature, f_g, increase with increasing size of the HB polyesters. It was shown that the modified HB polyesters exhibited lower T_g and T_G′=G″ temperatures, above which viscous became dominant over elastic behavior. From an analysis of the master curves of the modified HB polyesters, it was observed that with increasing degree of modification, both storage and loss modules and complex dynamic viscosity and apparent energy for viscoelastic relaxation decrease, because of reduced intermolecular hydrogen interactions. They do not exhibit a plateau of rubbery behavior, which confirms that no entanglements are present and that the molar masses are below the critical molar mass. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2015 , 132, 41479.     

Synthesis and characterization of hybrid films from hyperbranched polyester using a sol–gel process

Hybrid organic/inorganic materials were prepared by an in situ sol–gel process using tetraethoxysilane (TEOS) in the presence of hyperbranched polyester. The influences of hyperbranched polyester molar mass as well as the amount of TEOS were examined. The condensation degree was characterized by solid state ²⁹Si NMR. The combination of solubility tests, calcination tests, SAXS and dynamic mechanical analysis allowed us to investigate the hybrid material nanostructure. The results show high compatibility between the inorganic silica phase and the organic polymer phase, due to the spherical shape of the hyperbranched polymer and its numerous hydroxyl groups. As a consequence, a continuous inorganic phase was formed even with a low silica precursor content without any macroscopic phase separation. These hybrid materials have a high T_g and high storage modulus even at an elevated temperature combined with improved thermal stability. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014 , 131, 39830.     

Preparation of polyamidoamine dendrons supported on chitosan microspheres and the adsorption of bilirubin

The aim of this study was to prepare a new adsorbent for bilirubin (BR); low generation (G, G ≤4) hexanediamine‐containing polyamidoamine (PAMAM) dendrons were supported on chitosan (CS) microspheres (CS‐Gn, n = 0,1,2,3,4). The adsorption properties of this novel adsorbent for BR in aqueous solution were examined. The adsorption percentages were over 70% at 0.5 h and over 90% at 1 h. The adsorption capacity was up to 43 mg/g and was not yet saturated. The BR adsorption increased with increasing temperature and increasing BR initial concentration and was the highest at pH 7.4; it decreased slightly with increasing ionic strength and occurred even in the presence of bovine serum albumin (BSA). We observed that the CS–Gn microspheres had satisfactory competitive abilities with BSA, although the adsorption percentage decreased a certain extent in the presence of BSA. In addition, the CS–Gn microspheres were easier to prepare than the usual PAMAM dendrimers. In summary, this adsorbent is a promising biomedical material for BR removal for artificial liver supported systems. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013     

Solid–solid phase‐change materials based on hyperbranched polyurethane for thermal energy storage

A hyperbranched polyol (HBP) was synthesized with poly(ethylene glycol) (PEG) as the core molecule and 2,2‐bis(hydroxymethyl) propionic acid as the chain extender. Then, a series of hyperbranched polyurethane phase‐change materials (HP‐PCMs) with different crosslinking densities was synthesized with isophorone diisocyanate and HBP as a molecular skeleton and PEG 6000 as a phase‐change ingredient. ¹H‐NMR, gel permeation chromatography, and Fourier transform infrared spectroscopy confirmed the successful synthesis of the HBP and HP‐PCMs. The polarization optical microscopy and wide‐angle X‐ray diffraction results show that the HP‐PCM exhibited good crystallization properties, but the crystallinity was lower than that of PEG 6000. The analysis results from differential scanning calorimetry indicated that the HP‐PCMs were typical solid–solid phase‐change materials with suitable phase‐transition temperatures. In addition, HP‐PCM‐3, with an appropriate degree of hyperbranched structure, possessed the highest thermal transition enthalpy of 123.5 J/g. Moreover, thermal cycling testing and thermogravimetric analysis showed that the HP‐PCMs exhibited good thermal reliability and stability. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45014.     

Synthesis and properties of novel hyperbranched polyimides end‐capped with metallophthalocyanines

A fluorinated hyperbranched polyimide (HBPI) is synthesized by using a triamine monomer, 1,3,5‐tris(2‐trifluoromethyl‐4‐aminophenoxy)benzene (TFAPOB) (B₃), as a “core” molecule, 4,4′‐oxydiphthalic anhydride (ODPA) as a A₂ monomer, and 4‐aminophthalonitrile as an end‐capping reagent. After that, a series of novel fluorinated hyperbranched polyimides end‐capped with metallophthalocyanines were prepared by the reactions of dicyanophenyl end‐capped hyperbranched polyimide with excessive amounts of 1,2‐dicyanobenzene and the corresponding metal salt in quinoline. The resulting polyimides containing metallophthalocyanine unites shows optical absorption in the visible region. The absorption bands of the polymers in chloroform solution are in the range of 665–701 nm. These polyimides show glass transition temperatures between 216 and 225°C, and the 5 wt % weight loss temperature of the polymers varied from 440 to 543°C under nitrogen. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013